BEIJING  China will boost investment in wetlands protection and put more wetland areas under state protection in an effort to save them from destruction, state media said Thursday.

The official China Daily newspaper said that China's 66 million hectares (163 million acres) of wetlands are the largest in Asia and fourth-largest in the world.

However they are dwindling and lack protection, the Xinhua News Agency said in a separate report.

It said China has some 473 wetland nature reserves, giving protection to about 40 percent of its total wetland areas. The Chinese State Forestry Administration announced Wednesday it will increase the amount of protected wetland areas to 70 percent of the total by 2010, Xinhua said.

The government will also spend 9 billion yuan (US$1.1 billion;euro920 million) on wetlands conservation by 2010, the China Daily said, citing Zhao Xuemin, deputy director of the SFA.

China's rapid economic development over the last few decades has resulted in the mass destruction of millions of acres of farmland and wilderness and created some of the world's worst water and air pollution.

Tidal flats, swamps and marshes are considered wetlands. Wetlands are important for the environment because they provide homes for wildlife, serve as a natural filter systems for groundwater, and mitigate flooding at times of heavy precipitation.